Ultrasonic degradation kinetics and rheological profiles of a food polysaccharide (konjac glucomannan) in water

Jing Li, Bin Li, Ping Geng, Ang Xin Song, Jianyong Wu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

80 Citations (Scopus)


Upon the exposure of KGM solution (1% w/v in water) to US at a relatively high power intensity (50 W/cm2), the apparent viscosity decreased rapidly from about 50 Pa s to a negligible level within 10–20 min. The intrinsic viscosity ([η]) of KGM solution decreased gradually during the US exposure with a time course closely fitted to the first-order polymer degradation kinetics (random chain scission). The US treatment also caused a significant reduction of particle size (Zavg) of KGM aggregates and changes in the rheological properties including the decrease of storage modulus (G′) and loss modulus (G″), and the increase in phase angle (tan δ = G″/G′). Nevertheless, no change in primary structure was detected by Fourier transformation infrared (FT-IR) analysis. The results suggested that high intensity US was an effective means for KGM degradation without significant structural destruction.
Original languageEnglish
Pages (from-to)14-19
Number of pages6
JournalFood Hydrocolloids
Publication statusPublished - 1 Sep 2017


  • Polysaccharide
  • Rheological properties
  • Ultrasonic degradation

ASJC Scopus subject areas

  • Food Science
  • Chemistry(all)
  • Chemical Engineering(all)

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